Incidence and Risk Factors for Trocar Site Incisional Hernia Detected by Clinical and Ultrasonographic Examination.

Single-centre cross-sectional study based on prospective clinical and radiological assessment and retrospective risk factor analyses performed at a single hospital.

All consecutive patients who underwent laparoscopic surgery (cholecystectomy, colon resection, adrenalectomy, Nissen fundoplication and appendectomy) during a four months period were included in the study. At least 30 months after hospital discharge, they were invited by telephone to participate in the study. Detailed project information was provided, and those who accepted received an appointment for an outpatient visit and a dynamic ultrasound. Informed consent was obtained from all participants. In all patients, the umbilical trocar wound was closed with an interrupted suture with synthetic braided absorbable 2/0 suture (Novosyn® or Safil®). During the postoperative outpatient visit, clinical and ultrasonographic examinations were performed. To increase study homogeneity, all clinical examinations and ultrasounds were performed by a single surgeon and a single radiology resident supervised by the same abdominal radiology consultant, respectively. Sonography was performed with an Applio 500 equipment (Toshiba, Japan) with a 3.5MHz convex probe and a 7MHz linear probe. The ultrasound diagnosis was based on the identification of an abdominal wall defect with intraabdominal tissue protrusion. The main variables of the study were clinical (TSIHc) and ultrasound (TSIHu) diagnosis of incisional hernia. All results and variables were introduced in a previous specifically designed database (File MakerPro 11.0v3 © 1984-2011 FileMaker, Inc.). Data were collected from clinical interviews, physical and radiological examinations and the electronic medical record. Statistical analyses were performed using the SPSS statistical software (IBM SPSS® Statistics).